M.E. Sawan and M.A. Abdou, "Physics and Technology Conditions for Attaining Tritium Self-Sufficiency for the D-T Fuel Cycle", Presented at the Seventh International Symposium on Fusion Nuclear Technology, May
22-27, 2005, Tokyo, Japan; to be published in
Fusion Engineering and Design.
Abstract + conclusions:
"There is no practical external source of tritium for fusion energy development beyond ITER and all subsequent fusion systems have to breed their own tritium. To ensure tritium self-sufficiency, the calculated achievable tritium breeding ratio (TBR) should be equal to or greater than the required TBR. The potential of achieving tritium self-sufficiency depends on many system physics and technology parameters.
[...] It is clear from the above discussion that both
the required and achievable TBR values depend on many system physics and technology parameters. Many of these parameters are not yet well defined. In addition, the
rapidly decreasing tritium resources imply that the time window for the availability of tritium to supply fuel for the DT physics devices is closing rapidly. It is, therefore, necessary to establish without delay an extensive R&D program to determine the “phase-space” of plasma, nuclear, material, and technological conditions in which tritium self-sufficiency can be attained.
[...] Tritium self-sufficiency in DT fusion
systems cannot be assured unless specific plasma and technology conditions are met.
[...]
Page 32 of that presentation, "Tritium Supply Calculation Assumptions", says it is assumed that the following will NOT happen:
• Restarting idle CANDU’s
• Processing moderator from non-OPG CANDU’s (Quebec, New Brunswick)
• Building more CANDU’s
• Irradiating Li targets in commercial reactors (including CANDU’s)
• Obtaining tritium from weapons programs of “nuclear superpowers”
• Premature shutdown of CANDU reactors
But assumptions 3 and 4 have already been invalidated. China has added CANDU reactors since the presentation and is building a few more abroad for other countries. The United States has started irradiating lithium targets in commercial reactors.
So in my judgment, closing the tritium cycle still isn't on the critical path to fusion industrialization. There are other crucial problems to solve before "where will we get enough tritium for these fusion reactors?" becomes a crucial issue.
Well.
https://scholar.google.co.uk/scholar?hl=en&as_sdt=0%2C5&q=Sa...
http://fti.neep.wisc.edu/pdf/fdm1273.pdf
M.E. Sawan and M.A. Abdou, "Physics and Technology Conditions for Attaining Tritium Self-Sufficiency for the D-T Fuel Cycle", Presented at the Seventh International Symposium on Fusion Nuclear Technology, May 22-27, 2005, Tokyo, Japan; to be published in Fusion Engineering and Design.
Abstract + conclusions:
"There is no practical external source of tritium for fusion energy development beyond ITER and all subsequent fusion systems have to breed their own tritium. To ensure tritium self-sufficiency, the calculated achievable tritium breeding ratio (TBR) should be equal to or greater than the required TBR. The potential of achieving tritium self-sufficiency depends on many system physics and technology parameters. [...] It is clear from the above discussion that both the required and achievable TBR values depend on many system physics and technology parameters. Many of these parameters are not yet well defined. In addition, the rapidly decreasing tritium resources imply that the time window for the availability of tritium to supply fuel for the DT physics devices is closing rapidly. It is, therefore, necessary to establish without delay an extensive R&D program to determine the “phase-space” of plasma, nuclear, material, and technological conditions in which tritium self-sufficiency can be attained.
[...] Tritium self-sufficiency in DT fusion systems cannot be assured unless specific plasma and technology conditions are met. [...]